Various types of closures exist for containers. One common closure is a metal endpiece having a push-down tab or the like formed in its central panel and sized substantially less than the central panel. This type of endpiece is typically attached to an open end of a metal container body by a seaming operation, e.g., to provide a double seam between the end piece and the container body. Such closures are commonly used for both beverage and food containers. Re-sealing of such containers after opening the push-down tab typically involves use of a plastic over-cap separate from the endpiece.
Another common type of closure is a metal endpiece attached to a container body which may be formed from metal or composite materials (e.g., for various food products, including snack foods such as potato chips). A panel which is substantially the same size as the diameter of the container body is formed in the end piece and may be completely removed from the end piece by engaging an appropriate pull-tab or the like. In many of these designs, the remainder of the end piece provides some resistance or impediment to flow or removal of contents and/or presents sharp edges which may raise safety concerns. Re-sealing of such containers after removal of the panel typically involves use of a plastic over- cap separate from the end piece.
Removable plastic or foil membranes have also been utilized to seal various foodstuffs within a container. A plastic over-cap is typically involved in re-sealing the container after removal of a foil membrane.
Seals have also been provided between an end piece and a container body via some type of sealing member which is disposed between and separate from both the end piece and the container body. One type of sealing member which has been utilized is a sealing member strip which compressively engages a portion of the end piece against the container body. When removal of the end piece is desired, tension in the sealing member is increased to rupture a portion of the end piece engaged by the sealing member. This leaves the fractured portion of the end piece attached to the container body by the sealing member, and allows removal of the remainder of the end piece from the container body.
Another type of sealing member which has been commonly used in the juice industry is a simple plastic seal strip which is disposed between a metal end piece and a composite container body. The plastic sealing strip is pulled out from between the two members when removal of the end piece is desired.